Data/hora: 01/06/2024 18:32:52

Provedor de dados: | Brazilian Journal of Microbiology
País: | Brazil
Título: | Carbapenem and cefoxitin resistance of Klebsiella pneumoniae strains associated with porin OmpK36 loss and DHA-1 β-lactamase production
Autores: | Shi,Weifeng; Li,Kun; Ji,Yun; Jiang,Qinbo; Wang,Yuyue; Shi,Mei; Mi,Zuhuang.
Data: | 2013-01-01
Ano: | 2013
Palavras-chave: | Klebsiella pneumoniae; AmpC β-Lactamase; Porin; Molecular biology.
Resumo: | Clinical isolates of carbapenem-resistant Klebsiella pneumoniae (K. pneumoniae) strains are being increased worldwide. Five pan-resistant K. pneumoniae strains have been isolated from respiratory and ICU wards in a Chinese hospital, and reveal strong resistance to all β-lactams, fluoroquinolones and aminoglycosides. Totally 27 β-lactamase genes and 2 membrane pore protein (porin) genes in 5 K. pneumoniae strains were screened by polymerase chain reaction (PCR). The results indicated that all of 5 K. pneumoniae strains carried blaTEM-1 and blaDHA-1 genes, as well as base deletion and mutation of OmpK35 or OmpK36 genes. Compared with carbapenem-sensitive isolates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the resistant isolates markedly lacked the protein band of 34-40 kDa, which might be the outer membrane proteins of OmpK36 according to the electrophoresis mobility. In addition, the conjugation test was confirmed that blaDHA-1 mediated by plasmids could be transferred between resistant and sensitive strains. When reserpine (30 µg/mL) and carbonyl cyanide m-chlorophenylhydrazone (CCCP) (50 µg/mL) were added in imipenem and meropenem, the MICs had no change against K. pneumoniae strains. These results suggest that both DHA-1 β-lactamase and loss or deficiency of porin OmpK36 may be the main reason for the cefoxitin and carbapenem resistance in K. pneumoniae strains in our hospital.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822013000200015
Editor: | Sociedade Brasileira de Microbiologia
Relação: | 10.1590/S1517-83822013000200015
Formato: | text/html
Fonte: | Brazilian Journal of Microbiology  v.44 n.2 2013
Fonte: | info:eu-repo/semantics/openAccess